Dry clutch control for automotive applications.
The present book encourages the technology transfer in control engineering, by analyzing the control of a part of the power train, which has a key role in ride comfort. The book is divided into two main parts. The first one presents the mechanical elements of the driveline and describes a proper mathematical modeling. Before analyzing the clutch-related driving comfort, the authors study the interaction between the mechanical elements, during standing-start and gear shifting maneuvers. In the second part, the control problem concerning the dry clutch is discussed, first for the case of a synchronization-assistance model (only the clutch position is under control), and next for a fully automatic model. Chapter 2 gives a mechanical description of driveline elements and their interaction, with focus on the clutch. Here the reader can find a nonlinear model of the driveline for simulation, and a simplified model for control design, completed with a standing-start driver automation for closed loop simulation. Chapter 3 analyses the use of the clutch and the influence of driveline parameters. Chapter 4 presents a solution, called synchronization assistance, describing how the clutch comfort is affected by some physically interdependent elements. After the formulation of the dynamic equations and a quadratic cost function, the synchronization assistance strategy can be solved as a finite-time optimal control problem. The authors examine this problem by differential analysis, by Lagrangian multipliers, by matrix exponentials and by quadratic programming. In Chapter 5, the optimal standing-start is described by using exact dynamic replanning and a simplified dynamic replanning. Thus, the model-based predictive control can be studied by means of a control strategy that consists in solving an optimal problem in quadratic programming formulation for a liberalized system over a finite time horizon of some samples, and by issuing the first control samples before using the newly measured or estimated initial system state as a starting point for a new optimization. In Chapter 6, the authors describe a friction-coefficient observer, based on a multi-input/multi-output linear time variant extension of the class of observers known as adaptive observers for parameter controlled linear systems, and an input clutch torque observer. Finally, the above theoretical developments are illustrated in Chapter 7 by practical implementations and experimental results based on the Clio II 1.5 dCi prototype, equipped with a five-speed Renault AMT JH gearbox. Some conclusions and open problems are discussed in Chapter 8, such as the introduction of active elements in the clutch control system, which may lead to the possibility of several innovative solutions for improving the clutch comfort through a careful control of this additional degree of freedom. The estimation of transmitted torque by the clutch should be used not only for improving the standing-start performance, but also in order to increase the speed and comfort of gearshifts by matching the engine torque to the transmitted clutch torque. Appendices A, B and C present the mathematical background for some mechanical aspects. Appendix A emphasizes the optimization methods on which the mathematical model is based. Appendix B gives a proof of a theorem of Chapter 6. Finally, appendix C presents the dynamic friction model LuGre. The book could be of great interest to engineers working in automotive design as well as to academic researchers, due to the combination of theoretical results and interesting applications to the automotive control.
scientific article; zbMATH DE number 5688769